Need advice on DIY 295 CC bored to 350CC / 375

[Rooster59]

The 295 is 64mm bore by 46mm stroke, give or take a few thousandths of a mm. The 350 is 67mm by 49.5mm give or take. A 295 with std 350 pistons would be about 324cc.

Backwards calculations with known displacements and piston sizes.

[Gearhead1956]

Originally Posted by Rooster59

The 295 is 64mm bore by 46mm stroke, give or take a few thousandths of a mm. The 350 is 67mm by 49.5mm give or take. A 295 with std 350 pistons would be about 324cc.

Backwards calculations with known displacements and piston sizes.

I just checked CT Rebuilds web site and they do advertise a 375 that they say is a 295 with a std 350 piston!

I have to remember to call them and see whats up, just does not make sense!

[Rooster59]

I don't think they have ever claimed it is 375cc. Best I can remember they just call it a "375" to differentiate it from stock and support their claims of increased power.

Several members have purchased one and been pleased. But the number designation is a little misleading at a glance.

[Gearhead1956]

Originally Posted by Rooster59

I don't think they have ever claimed it is 375cc. Best I can remember they just call it a "375" to differentiate it from stock and support their claims of increased power.

Several members have purchased one and been pleased. But the number designation is a little misleading at a glance.

OK! I just called CT rebuilds and they told me the 375 engine is 375cc's

She said they bore the 295 to fit a stock 350 piston and do some other machining to the head!
She stated that a stock 295 compression ratio is 9 to 1, a 350 is 10 to 1 and their 375 is 10.4 to 1

Also stated that a 350, .0025 over would be the same CC's

I am no expert here, but I don't see how putting a stock 350 piston in a 295 would come out to more then a 350 unless the 295 crank has a longer stroke?? You could cut the head to get more CC's but that would lower the compression.

can someone please explain this?
Ok I just put a stock 295 piston down in a 350 block, turned the crank and the piston came just to the top of the block, as normal. So the crank stroke must be the same on both engines. the part number for the rods 295/350 are the same.

[Rooster59]

The stock 295 piston is 64mm in diameter. The stock 350 piston is 67mm in diameter. No way can those two engines have the same stroke to achieve the displacement claimed by EZGO.

I will let you decide.......

http://performancetrends.com/Calcula...splacement.php

[Gearhead1956]

Originally Posted by Rooster59

The stock 295 piston is 64mm in diameter. The stock 350 piston is 67mm in diameter. No way can those two engines have the same stroke to achieve the displacement claimed by EZGO.

I will let you decide.......

http://performancetrends.com/Calcula...splacement.php

I agree, no one seems to have the answer's. I can't find the answers!

You think its all BS? LOL

I have a 350 apart now and can measure the stroke on it, if someone has a 295 apart and could do the same we would have it, maybe?

It makes me nuts when I can't find real accurate answers!

[Mrlzybones]

The 350 crank has a longer stroke. Weist pins on the 350 piston are higher. Essentially if you ran a 295 crank with 350 piston the block would need to be decked so piston reaches deck height of the block. The 295cc has approx. .300 less stroke. I've taken my 295cc bored to 350 pistons using the 350 crank. I double stacked head gaskets and am quite happy with the performance.

[Mrlzybones]

Because the rings set lower on the 350 (67mm) pistons your able to utilize the extra stroke without fear of ring failure. Rings down wrist pins up. Rods are identical length on both 295/350. Its all in bore diameter & proper crankshaft to reap the benefits of 67mm pistons in 295cc block.